Asteroid YU55 coming, will swing nearer to Earth than the moon

On Tuesday, the asteroid known as YU55 will come closer to our planet than any other asteroid has come since 1976.

Of course, when it comes to outer space, "close" is a relative word. Scientists at the Jet Propulsion Laboratory in Pasadena say YU55 will come within 201,700 miles of Earth and no closer. That's nearer than we are to the moon, but far enough away to eliminate the possibility of a collision.

"We know exactly where it is going to be, and we don't have any chance of impact for the following hundred years," Marina Brozovic, a scientist and member of the JPL Goldstone radar team, told The Times. Her team plans to track the asteroid beginning Friday.

"It is just a great scientific opportunity. It is really, really exciting."

Asteroids are basically space rocks -- debris created when the solar system was formed. YU55 is a moderate-size asteroid -- about 1,300 feet wide, or about the width of four football fields stretched end to end. Radar images taken in 2010 by the Arecibo Observatory in Puerto Rico revealed that it appears to be spherical in shape and rotates in about 18 hours.

That same year, an optical telescope revealed the rock to be a C-class asteroid, meaning it's probably darker than charcoal and contains a lot of carbon.

Part of the reason YU55 is so interesting to the scientific community is because similar asteroids played a major role in our planet's past, and they have the potential to play a major role in the future of humankind.

Don Yeomans, manager of NASA's Near-Earth Object Program Office, said that asteroids colliding with Earth in the extremely distant past may have been responsible for bringing the water and carbon material that has made life on the planet possible.

And in the future, scientists say, these asteroids may serve as watering holes and fueling stations for interplanetary travel.

"We may one day be able to mine asteroids, and if we start colonizing the solar system, they will be our fueling stations," Brozovic said.

You won't be able to see YU55 without a telescope, but be on the lookout for pictures of what scientists will be seeing.

"It's really quite an opportunity," Yeomans said in an interview with The Times. "It's not very often that something this good gets this close."